相关链接
联系方式
  • 通信地址:天津市津南区海河教育园区雅观路135号天津大学北洋园校区化工学院
  • 邮编:300350
  • 电话:022-
  • 传真:022-
  • Email:renxiangkui@tju.edu.cn
当前位置:> 首页 > 论文著作 > 正文
Homopolymer and Random Copolymer of Polyhedral Oligomeric Silsesquioxane (POSS)-Based Side-Chain Polynorbornenes: Flexible Spacer Effect and Composition Dependence
作者:Xiao-Hui Zheng, Jian-Feng Zhao, Ti-Peng Zhao, Tao Yang, Xiang-Kui Ren*, Chen-Yang Liu, Shuang Yang*,
关键字:POSS
论文来源:期刊
具体来源:Macromolecules
发表时间:2018年

A series of homopolymers and random copolymers of polyhedral oligomeric silsesquioxane (POSS)-based side-chain polynorbornenes were prepared using ring-opening metathesis polymerization. For the homopolymer P-z-POSS (z represents the spacer length, z = 5, 12, 17), the POSS groups tethered to the side-chain are linked to the polynorbornene backbone through the flexible spacer with different lengths. For the random copolymer P-6-co-17(X/Y) (X/Y = 1/1, 3/1, 6/1, 9/1), the composition was regulated by adjusting the molar feed ratio X/Y of the norbornene monomer with butyl ester side group (M-6) to the POSS containing monomer with the longest spacer (M-17-POSS). Using various techniques, we studied the spacer length effect on POSS crystallization of the homopolymers and the composition dependence of physical properties of the copolymers. It is found that P-5-POSS is amorphous. On the contrary, POSS crystallization is observed in P-12-POSS and P-17-POSS, and the longer the spacer is, the higher the POSS crystallization ability is. With the co-monomer of M-17-POSS, all the P-6-co-17(X/Y) samples can have the POSS group to crystallize, resulting in a nano-segregation similar to the lamellar morphology. The lamellar period is inversely proportional to the POSS volume fraction. The POSS crystallites are raft-like, containing two layers of POSS groups stacked together. Uniaxial stretching can well align the POSS crystallites in the copolymers to be parallel to the stretching direction, and the lamellar period is decreased with increasing the strain. Varying X/Y from 1/1 to 9/1 changes the copolymer from plastic to thermoplastic elastomer, wherein the later takes the POSS crystallites as the physical cross-links.